2021 Volume 67 Issue 3 Pages 432-439
Screening of platelet concentrate (PC) for bacterial contamination is not currently performed in Japan. We evaluated the validity of screening PCs using the automated blood culture systems BacT/ALERT 3D (3D) and BacT/ALERT VIRTUO (VIRTUO). We compared the time to detection (TTD) of bacteria between the two systems, and then validated the screening protocol by testing bacteria-spiked PC bags using VIRTUO. In the comparative test, four bacterial species at two different concentrations were inoculated into aerobic and anaerobic culture bottle sets and 5 sets each were tested using 3D and VIRTUO. The TTD was significantly shorter for all bacterial inoculum using VIRTUO than 3D, demonstrating the superiority of VIRTUO. In the validation test, PCs inoculated with bacteria were tested using VIRTUO at 40h post-spiking. All four bacterial species were detected within 24 hours if the spiked bacteria had grown to a concentration >10CFU/ml after storage.
Our results indicate that, although there is a possibility of missing slow-growing bacteria, bacterial screening of PCs stored for a certain period of time using VIRTUO is expected to reduce the risk of transfusion-transmitted bacterial infection.
